1. Field of the Invention
This invention relates to a catheter for nasogastric intubation.
2. Description of the Prior Art
Normally, a catheter for nasogastric intubation for supplying nutrition comprises a weight portion in which the weight is sealed into a distal end of a soft small-diameter plastic tube. The tube is inserted from a nostril into the stomach or the intestines, making use of its weight, so as to supply nutrition through one or two side holes positioned slightly above the weight portion.
Since the catheter is kept placed through the nostril for a long period of time, a patient feels a considerable pain. To relieve this pain, it is preferable that the catheter be formed of a material as soft as possible. Further, since the catheter is kept in contact with the walls of the internal organs for a long period of time, if the catheter is formed of a hard material, the tissue of the walls of the internal organs may be damaged. For this reason, the catherter should be formed from a soft plastic tube. However, since the soft plastic tube lacks stiffness, it is difficult for the soft tube to be inserted since it must pass into the greatly bended stomach and intestines, through the oesophagus beyond the narrow-passage larynx, and through the nostril.
For this reason, in a conventional method, a guide wire is inserted into the inner cavity of the catheter to increase stiffness. However, in this method in which a guide wire is moved into the catheter, a lubricant has to be coated on the internal surface of the catheter to decrease the frictional resistance between the wire and catheter and in addition, insertion of the guide wire is cumbersome.
Furthermore, there is a danger that when inserting the guide wire, the end of the wire may project from the side holes of the catheter and pierce the walls of the internal organs.